Buggy code:
public final class JavaCore extends Plugin implements IExecutableExtension { private static final String JAVA_CORE_INIT = "JavaCore.ini" ; private static Plugin JAVA_CORE_PLUGIN = null ; public static final String PLUGIN_ID = "org.eclipse.jdt.core" ; public static final String BUILDER_ID = ( JavaCore . PLUGIN_ID ) + ".javabuilder" ; public static final String MODEL_ID = ( JavaCore . PLUGIN_ID ) + ".javamodel" ; public static final String NATURE_ID = ( JavaCore . PLUGIN_ID ) + ".javanature" ; private static final String ATT_HANDLE_ID = "org.eclipse.jdt.internal.core.JavaModelManager.handleId" ; private static Hashtable Variables = new Hashtable ( 5 ) ; public JavaCore ( IPluginDescriptor pluginDescriptor ) { } public static void addElementChangedListener ( IElementChangedListener listener ) { } public static void addJavaElementMarkerAttributes ( Map attributes , IJavaElement element ) { } public void configureJavaElementMarker ( IMarker marker , IJavaElement element ) throws CoreException { } public static IJavaElement create ( String handleIdentifier ) { } public static IJavaElement create ( IFile file ) { } public static IJavaElement create ( IFolder folder ) { } public static IJavaProject create ( IProject project ) { } public static IJavaElement create ( IResource resource ) { } public static IJavaModel create ( IWorkspaceRoot root ) { } public static IClassFile createClassFileFrom ( IFile file ) { } public static ICompilationUnit createCompilationUnitFrom ( IFile file ) { } public static IPackageFragmentRoot createJarPackageFragmentRootFrom ( IFile file ) { } private static IJavaElement determineIfOnClasspath ( IResource resource , IJavaProject project ) { } public static IPath getClasspathVariable ( String variableName ) { } public static String [ ] getClasspathVariableNames ( ) { } private static IPath getInstallLocation ( ) { } public static JavaCore getJavaCore ( ) { } private IJavaProject getJavaProject ( IProject project ) { } public static Plugin getPlugin ( ) { } public static IClasspathEntry getResolvedClasspathEntry ( IClasspathEntry entry ) { } public static IPath getResolvedVariablePath ( IPath variablePath ) { } public static boolean isReferencedBy ( IJavaElement element , IMarker marker ) throws CoreException { } public static boolean isReferencedBy ( IJavaElement element , IMarkerDelta markerDelta ) throws CoreException { } public static IClasspathEntry newLibraryEntry ( IPath path , IPath sourceAttachmentPath , IPath sourceAttachmentRootPath ) { } public static IClasspathEntry newProjectEntry ( IPath path ) { } public static IRegion newRegion ( ) { } public static IClasspathEntry newSourceEntry ( IPath path ) { } public static IClasspathEntry newVariableEntry ( IPath variablePath , IPath variableSourceAttachmentPath , IPath sourceAttachmentRootPath ) { } public static void removeClasspathVariable ( String variableName ) { } public static void removeClasspathVariable ( String variableName , IProgressMonitor monitor ) { } public static void removeElementChangedListener ( IElementChangedListener listener ) { } public static void setClasspathVariable ( String variableName , IPath path ) throws JavaModelException { } public static void setClasspathVariable ( String variableName , IPath path , IProgressMonitor monitor ) throws JavaModelException { } public void setInitializationData ( IConfigurationElement cfig , String propertyName , Object data ) throws CoreException { } public void shutdown ( ) { } private void startIndexing ( ) { } public void startup ( ) { } private static void updateVariableValue ( String variableName , IPath path , IProgressMonitor monitor ) throws JavaModelException { } public static IJavaModelStatus setOptionValue ( String id , String value ) { } public static String getOptionValue ( String id ) { } private static IJavaModelStatus setOptionDefaultValue ( String id , String value ) { } public static String getOptionDefaultValue ( String id ) { } public static String getOptionDescription ( String id ) { } public static String getOptionName ( String id ) { } public static String getOptionComponentName ( String id ) { } public static String getOptionCategory ( String id ) { } public static String [ ] getOptionPossibleValues ( String id ) { } public static String getOptionType ( String id ) { } public static Number getOptionMax ( String id ) { } public static Number getOptionMin ( String id ) { } public static String [ ] getOptionIDs ( ) { } public static String [ ] getOptionIDs ( String componentName ) { } public static IJavaModelStatus validateOptionValue ( String id , String value ) { } public static void resetOptions ( ) { } private static void setJavaCoreDefaultOptionsValue ( Locale locale ) { } private static Hashtable getOptions ( ) { if ( ( fOptions ) == null ) <START_BUG> setOptionsToDefault ( ) ; <END_BUG> return fOptions ; } private static ConfigurableOption [ ] getDefaultOptions ( Locale locale ) { } }

Fix:
JavaCore . resetOptions ( ) ;